Concrete is used to construct a variety of structures, such as building walls and floors, bridge supports, dams, columns, raised platforms and the like. Typically, concrete structures are formed using embedded reinforcement bars (often referred to as rebar) or similar steel reinforcement material, which provides the resultant structure with increased strength. Over time, corrosion of the embedded reinforcement material can impair the integrity of the embedded reinforcement material, the surrounding concrete and the overall structure. Similar degradation of structural integrity can occur with or without corrosion over sufficiently long periods of time, in structures subject to large forces, in structures deployed in harsh environments, in structures coming into contact with destructive materials or the like.
FIG. 1 shows an example of a damaged concrete structure 10. Structure 10 is generally rectangular in cross-section and comprises undamaged in section 10A and damaged in section 10B. The damage to structure 10 has changed the cross-sectional shape of damaged section 10B. While damaged section 10B remains generally rectangular, its surface profile is relatively uneven. In some portions 12 of structure 10, the concrete damage is sufficient to expose reinforcement material 14 (e.g. steel rebar).
There is a desire for methods and apparatus for repairing and/or restoring concrete structures which have been degraded or which are otherwise in need of repair and/or restoration.
Some structures have been fabricated with inferior or sub-standard structural integrity. By way of non-limiting example, some older structures may have been fabricated in accordance with seismic engineering specifications that are lower than, or otherwise lack conformity, with current seismic engineering standards. There is a desire to reinforce existing structures to upgrade their structural integrity or other aspects thereof.
There is also a desire to protect structures from damage which may be caused by, or related to, the environment in which the structure is deployed and/or the materials which come into contact with the structure. By way of non-limiting example, structures fabricated from metal or concrete can be damaged when they are deployed in environments that are in or near salt water or in environments where the structures are exposed to salt or other chemicals used to de-ice roads.
Structures for which it is desirable to repair, restore, reinforce and/or protect are not limited to concrete structures. There are similar desires for structures fabricated from other materials.